Electronically they are not that complex (ie theory of operation), troublesome part is wiring - you don't have Chinese sweatshop workers/nearby technical school internes building your prototypes at enthusiast's lab, so it takes ages of mindless work to for example wire all the switches from the keys. Copy and paste of 50 switch debounce doesn't make project complex, it just makes it awful to build (hence Ben didn't use bucket of 555s because of time constraints):)
I don't think the thermal stability requirements are actually that difficult compared to, say, anything involving radio. Not sure how this ended up so drifty.
It's practically impossible to build a 555 based keyboard that size without trim pots and just resistors. As you mentioned, the resistors very sensitive to heat, hence need easy access tenability of every key vs 1% variance resistors etc.
That. Would be extremely interesting to see what kind of feature set and interface could come up someone who is really digs the old stuff and knows all ins and outs. Would totally help with that, even.
The old analogue synths often had something like a thermistor bonded to the main oscillator chip(or transistor array) to compensate for temperature drift. This is a project that they could have done better with a Raspberry PI/or micro controller or if they had done more research they could have just implemented a single oscillator analogue control voltage and gate system. Glad they tried anyway.
An Arduino would've been perfect as a controller yeah. They also could've gone the Roland Juno/organ route and have an master oscillator with a bunch of divide down circuits to generate the notes.
And for the rest of us, who aren't that neat with a soldering iron and figuring out how to make an analogue synth from scratch... there's the DIY MS-20 among other kits. If only I had some extra cash lying about... ;) www.korg.com/us/products/dj/ms_20kit/
What an appropriate name for a keyboard that looks like the Fresh Prince Of Bel-Air and sounds like a Gameboy with a cold. I'm all for chiptunes, it's easily 25% of my music library, but this is just a weird bad novelty thing. Still a cool video though!
the design this is based on is very unpredictable temperature and humidity can change the sound drastically. i bought a shipping box of 555 timers to make one of these keyboards but with full polyphony, thats a project i need to finnish.
Yes, a simple oscillator design like this is going to be temperature-sensitive. You could get away with it with vacuum tubes because they generate their own heat and thus are less sensitive to the ambient temperature, but with solid-state circuitry, just putting your finger on the transistor or IC will warm it up enough to cause it to change frequency!
VWestlife yes the unpredictability of it is its weakness but also its charm the prototype i made of my project were all linked together thermally and coverd in heatconducting epoxy to keep it reasonably thermally stable.
VWestlife yes the unpredictability of it is its weakness but also its charm the prototype i made of my project were all linked together thermally and coverd in heatconducting epoxy to keep it reasonably thermally stable.
There are ways to compensate for this. One way is to use resistors with a very specific change in resistance by temperature. They call them tempco resistors. Design your circuit around these tempcos and you can get a stable analog signal within a given temperature range. Another way is to actually "take charge" of the heating using a heat source and a feedback loop (typically a DAC connected to a CPU). When the DAC tells you you're too cold, you increase the current through the heat source, and when the DAC tells you you're too hot, reduce the current. That way the chip stays at a consistent temperature, regardless of ambient temperature.
No its because of bad circuit design. The adjustment is way too coarse. If one of the pots just drifts by 0.1% the frequency will be off. The adjustment range needs to be much smaller and you need to use low drift components.
@@kristoffere9996sorry to reply to such an old comment but the name atari junk keyboard is a play on the atari punk console, which is a very simple and common 555 based noisemaker; this is an atari punk console (or a few dozen) made with a junk keyboard, so,, atari junk keyboard 👯♀️
you guys are 2 of my favorite youtube channels, it was epic to see a crossover between them! like many people, i was hoping to hear that atari keyboard make an actual song, so here it is! thanks 8-bit guy/keys :)
Not saying Felix isn't a really smart person, but Ben is sorta meant to be the "brains" of the show while Felix is the "brawn". They're both really clever and Felix knows a lot more about programming languages than Ben, but he does the dirty work most of the time.
The sound reminds me of a Stylophone (now there's something you could try out!), terrible, but unique, which is what makes it work, well, 'til it conked out of course... :)
555 chips rely on capacitor discharge time to generate a pulse and if flat ceramic caps are used then the timing will be greatly affected by the ambient temperature.
this is great! I've been a ben heck fan for years, and was featured on one of his episodes. he claimed back then that he's no good at music and wouldn't do a music-related project - I'm glad he finally did!
as I recall from bens vid, it uses the 555 timer chip 4 sound, so other waveforms ar not nearly as easy to do as you would think. and if you say he used 556 not 555, their the same thing, but 556 hat 2 555's in it.
I guess building 12 oscillators and then dividing down with a flip flop would make more sense. You'd still need some sort of VCA per key then... Part count gets out of hand fast, indeed. Although, old transistor organs did something similar.
I am planning to create my own keyboard, similar to that one but using an ATtiny, polyphonic etc. If I send it to you when I am ready, would you send it back to me later?
I have thought about it for some time but I got to ask. It would be great to see how you go about composing. I mean, what are your routine go to stuff (key, chord progression, melody relationship to chords)? you have distinct style/ sound to your melodies.
Great collab with Ben Heck When I saw the keyboard i had to think it would be nice if you got to test it, pity you couldn't actually do a whole song on it ^^ but was a great demo!! Also, absolutely loving the amount of videos you've been pumping out lately man, best luck on your endeavors!
Cool project. I did something similar to that about 20 years ago. It only used 1 555 timer for a clock source and 4 chips called "top octive dividers". They were intended for the highest octive and to get the next lower octive divide each note by 2, but I divided the clock source by 2 for each octive. I fed each note through a keyboard from an organ to 44 100k resistors as a mixer. I only needed to adjust one pot to tune the whole kb and got full 44 note polyphonic output..
If you want to see what goes into a single-voice analog synthesizer, with temperature compensation (yes, analog synths tend to go out of tune at different temperatures unless compensated using special tempco resistors), check out MFOS (Music from Outer Space). Ray has passed on, but this Sound Lab Ultimate is still an excellent example of analog electronics. He also has keyboard scanning circuits, noise generators, and more. The schematics and board layouts are all on his site. Also, analog synthesizers with VCOs (starting in the 80s) typically have tuning logic on-board. It's usually a microcontroller doing some sort of frequency counter stuff and adjusting voltages to compensate.
Phaedra by Tangerine Dream is supposed to have started out as a practice demo also! But I don't think the keyboard broke on them. The Moog suddenly starts going out of tune at one point and they mixed it so that it seems like they did that deliberately.
Not really, he's just saying as a practical keyboard it's junk as you nead more polyphony and it needs to stay in tune and all that. But he's also saying that as a proof of concept its a really good idea that he enjoyed playing around with. Ben says its not as good as it could be due to his self imposed time limit and design choices to make it a quicker build. He does a llt of projects and cant afford yto get bogged down.
Eh, not really. It was a quick build, it is just a concept. I'm sure Ben and Felix just wanted to see if they actually could build a keyboard before they started building something more advanced and bigger.
It was a bit blunt perhaps, but to be honest, it was kind of a ridiculous design on Ben's part. Especially if they were on a time crunch, it seems like they actually made it way more complicated than it really needed to be, and made it worse as a result.
Daniel G That I can agree on. There were some things that they could've done better just as fast, but I still think it's an interesting concept with no microchips or anything!
Mmm, jury's out still. I like 8bit guy tons but Ben really knows his stuff so sounded a bit "meh" when in fact with time constraints it was very well executed - and 8bit guy probably couldnt do it himself in that timeframe.
Analogue synths were notorious for going out of tune and changes in ambient temperature, heat or humidity were the main culprits of making a synth go from fine, half an hour ago, to discordant chaos considering it was toasty inside the synth now. Hot and cold days played murder with voltage controlled oscillators. IC's (LM555's or LM556's) and digitally controlled oscillators finally sorted things out. You should look at a device called a dub siren. It's a single oscillator squeaky thing (with loads of delay on it) all over reggae records. An LFO modulates an oscillator and makes all manner of mad sounds. Look for the RUclips vid 'NJD Style Dub Siren - Sound System FX' for a demo if you are interested.
The Ben Heck Show stuff is allways interesting and they have a lot of knowledge- BUT I allways think they put not enough thought in their concepts to make a good result- and than they ALLWAYS rush things an make stuff kind of useless in the end....
mario64remix nothing except one of the original designers who came up with the schematics thought it sounded vaguely like a 2600 after they built it and the name stuck. Search "Atari punk console" on Wikipedia if you want more info
COUGH COUGH!!! Original designers my ass....Forrest Mims designed this circuits and published it in a series of cool little electronics schematics book, published in 1980 to look like someones hand drawn notes. At some point some people hit on this circuit and started selling kits of it to make money out of someone else's design, give it a stupid name, and inspire a million numbskulls to make horrendous sounds with this god awful design. I include myself in that. The best thing I ever did was throw away all my 555 chips, although someone did actually manage to make the 555 chip sing, the Thomas Henry 555 VCO is an osciallator worth playing, it;s a much more complicated build than this however (and way more expensive) but if they could build a keyboard that had 4 of those, which could be either across the 4 octaves or put into some unison mode, they would build a serious contender for a worthy synth. Akai released something like that which famously sounded awful at NAMM as it never kept tune at all, all the demo videos are beyond funny, I don't know if they ever released that synth, but surely these guys could build something better than it.
The pots are logarithmic meaning that at the lower end the ohm values are spread out and at the upper end there are close together. Replace them with linear pots and you'll be able to tune the notes at the upper end.
yeah. Why is everyone being so harsh to Ben & Felix. It's such an awesome project, and it works quite well. It could've even been shipping that caused it to fail. It doesn't even have a sound chip and it still sounded good. I doubt 90%+ of everyone watching this video can actually comprehend how to build a keyboard of their own like Ben & Felix did. So much disrespect in the comments. It's like telling an artist their art is shit when it's their first time trying out watercolour; instead of the usual pencil drawings. Ben isn't technically a professional in the field of music, but he is at pretty much everything else to do with electronics. People are being way too harsh
That may all be true but this is intended to be a musical instrument, it serves a single purpose and it should be judged by its performance. If someone enginered a midi guitar but didnt bother with proper fretboard then it would be useless defeating the purpose of engineering it. As a viewer I see this video as showcasing a prototype which is nonfunctional.
Ben Heck - over complicated and over engineered solutions to problems that do not exist. He's done some great things, but builds like this just seem pointless.
When just using circuitry without any sort of computronics, you can expect this sort of inaccuracy. That said, this was really neat, and pretty damn sweet.
Radio Shack used to sell a keyboard kit which used *one* potentiometer and a bunch of 5% resistors--I think I got that one for my birthday and it was a real disappointment since it couldn't achieve anything remotely musical. With regard to the BH design, intonation could likely be improved considerably by using smaller capacitors on the higher octave generators (cut the capacitance by about half for each octave). Basically try to use the smallest cap on each generator that will still allow it to be tuned to the correct note. Otherwise, if one wanted full polyphony it could easily be achieved using 12 74HC4060 chips for a chromatic scale, or 7 for a diatonic scale; each chip would provide outputs for one pitch in seven consecutive octaves.simultaneously.
This was a great video but crap keyboard worthy of the dumpster. Time restraints or not Ben Heck but if you're going to build something, DO IT RIGHT!!!!!!.
Where does Atari come in place? Did I miss something? Btw, that is actually an immature and next to useless device. Rather a waste of time, honestly. In respect for the effort involved I hesitate becoming explicit. If you do something, do it right.
I cant remember the details but the keyboard is essentially using the same method to create sound that the old Atari used. This was more a prototype to see if it could be done, a lot of effort but they learnt things and created something interesting.
Waste of time for you, maybe, but not for the people who made it, nor the people who watched the episodes and learnt a lot about simple electronics in the process. The nerve of some people...
ComandanteJ Please don't get me wrong, I honestly and totally respect the effort and the skills coz I could not achieve anything even close to working status. But this doesn't render the device useful. And srsly no disrespect at all to the creators. But I couldn't say "Great Job!". Could you?
"I honestly and totally respect the effort and the skills" Then act like it, instead of being a pretentious jerk. This isn't something that's supposed to have a utilitarian purpose. It's for fun and also serves as a teaching tool for basic electronics.
this reminds me a lot of a synth i built in university. the more pots you use, the worse it gets hahaha. i built a very simple 2 oscillator polyphonic synth, wanted to do 2 octaves but even cheap parts are expensive. the polyphony ended up working alright (but adding waves meant you would have to lower amplitude somehow), and i even ended up having it generate some cool polyrhythms as a result of the waves adding the way they did. the synth was glued onto a plank of wood and i think most of the cables are now missing. but watching this was a cool trip down memory lane
Awesome work David! Love your videos! Any chance you might do a review or demos of any of the Roland AX series "keytars" some day? I've seen a pair played live by Freezepop and they were incredible, I'd love to hear your take on them.
A company in Italy called farfisa was building all electronic organs, without the use of any digital circuitry, or even integrated circuits, half a century ago. These devices used initially germanium transistors, which were supplied by Mullard of the UK, and eventually switched to modern silicon transistors. Schematics are readily found on the internet, and they are excellent examples of electronics as an art form. Even today, surviving units are prized because of what is called the farfisa sound.
A 555 timer chip depends on an external capacitor / resistor hystereses to induce oscillation within the 555 chip. If the components used for this are physically small the tuned frequency will change not only as a result of ambient temperature but also as the components warm up with use. This will be most noticeable if the cap is a ceramic type because then ambient humidity will increase this effect. The only way to stabilize a 555 timer IC is to replace the capacitor with a crystal. This would prevent tuning in all but harmonics of the natural crystal frequency. The 555 IC is a linear circuit with a digital output. The linear portion of the 555 are affected by temperature changes as well. The high octave tuning sensitivity problem could be solved by using linear potentiometers rather than logarithmic pots. The effect of two keys side by side pressed at the same time resulting in the played note being approximately one octave higher is because you are applying two of the tuning pots in parallel to a single 555 timer IC. This effectively divides the resistance in half and rises the oscillation frequency of the capacitor by a factor of 2 (or one octave)
Two problems here: 1, there is a resistance scaling problem due to nonlinearity of the RC time constants thru-out the musical range (5-8 octaves). 2, the octave allocation is asynchronous or random with the keying input. Diode isolators are needed between resistors so adjacent notes don't interfere with each other by altering the RC time constants (reducing resistance).
Trent Reznor could probably appreciate a synth like this, he uses a Swarmatron quite frequently in his music, it doesn't have much electronics, just a spider circuit board with relays and knobs.
This makes you appreciate the hard work those Yamaha engineers did back in the 80s. Building keyboards is hard.
Electronically they are not that complex (ie theory of operation), troublesome part is wiring - you don't have Chinese sweatshop workers/nearby technical school internes building your prototypes at enthusiast's lab, so it takes ages of mindless work to for example wire all the switches from the keys. Copy and paste of 50 switch debounce doesn't make project complex, it just makes it awful to build (hence Ben didn't use bucket of 555s because of time constraints):)
I don't think the thermal stability requirements are actually that difficult compared to, say, anything involving radio. Not sure how this ended up so drifty.
Not really the same thing. Yamaha keyboards at the time, bar their analogue synths, used FM soundchips, firmware etc.
How about VCRs and mostly CRT TVs?
Just imagine the pain in the ass it was to make the teleharmonium...
The keyboard has a mind of its own. Whatever you do don't connect it to the internet.
the keyboardnator
Skyboard 2.0
Play this note if you want to live!
Awesome sound never dies :-)
Are you sure you didn't borrow the HAL 9000 musical keyboard? 😆😛
you could play some really dank dial-up sounds o that...
lol
😂😂🤣
It's practically impossible to build a 555 based keyboard that size without trim pots and just resistors. As you mentioned, the resistors very sensitive to heat, hence need easy access tenability of every key vs 1% variance resistors etc.
"press them down together... what tone is that?" annoying... that's the tone it is
Ryan Fiscus Not everyone has perfect pitch.
*The 8-Bit Guy would like to know your location*
@@andrewbarrett1537 that wasn't the point but ok
The tone is slightly different, yes.
It's the sound of a Wii crashing
"This is the most unique keyboard I'll probably ever play on this show"
*Immediately writes on it in permanent marker*
unique = value
He wrote on a piece of tape bruh
@@DanJFilms first he wrote on the piece of wood and then placed a piece of tape because he made some mistakes along the way.
@@alextator9015 That's what killed me. He said it was one of a kind.
Then again it was made with literal trash
I love Felix as his dry sense of humor.... "Bummer" had me chuckling way too much :p Great to have two of my favorite youtubers doing a colab video!
I see an opportunity to spam ppl, i take it
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Skxjcjeiei
Should’ve played the crazy bus theme song
amazing lol
both 8-bit keys and the 8-bit guy channel are 2 of my favorites to watch. keep up the great work
Did you know it's the same guy on those channels?
Bazahaza yes i know it's the same guy.
;-)
Don't forget about "the ibookguy"
SwiftHelix the iBook guy is the 8-bit guy
You should try and make your own keyboard man. It would be cool to see the "8 bit keys" keyboard
That. Would be extremely interesting to see what kind of feature set and interface could come up someone who is really digs the old stuff and knows all ins and outs. Would totally help with that, even.
Let's play Famicommodore on it.
The old analogue synths often had something like a thermistor bonded to the main oscillator chip(or transistor array) to compensate for temperature drift. This is a project that they could have done better with a Raspberry PI/or micro controller or if they had done more research they could have just implemented a single oscillator analogue control voltage and gate system. Glad they tried anyway.
An Arduino would've been perfect as a controller yeah. They also could've gone the Roland Juno/organ route and have an master oscillator with a bunch of divide down circuits to generate the notes.
Show don't tell. If you can do better, build it.
Yes, but the whole point of this project was to build it from simple circuites, not just toss in an arduino and make it perfect
@@varkokonyi an analog oscillator that can track 1V/octave is kinda easy to make, it would need just a few more components.
It looks like the point was to do it with all analog electronics. Of course you can make a better synth on a microcontroller.
And for the rest of us, who aren't that neat with a soldering iron and figuring out how to make an analogue synth from scratch... there's the DIY MS-20 among other kits. If only I had some extra cash lying about... ;)
www.korg.com/us/products/dj/ms_20kit/
That was seriously awesome. You guys should do more crossover episodes!
And I hope one day I'll see Clint cosplaying as Ben Heck.
What an appropriate name for a keyboard that looks like the Fresh Prince Of Bel-Air and sounds like a Gameboy with a cold. I'm all for chiptunes, it's easily 25% of my music library, but this is just a weird bad novelty thing. Still a cool video though!
Gameboy with a cold... I couldn't have said it better myself.
More like Saved by the Bell and Fresh Prince's baby lol
This is 1-bit Key!!
the design this is based on is very unpredictable temperature and humidity can change the sound drastically. i bought a shipping box of 555 timers to make one of these keyboards but with full polyphony, thats a project i need to finnish.
Well maybe you can... _swedish_ it (sorry, for the terrible pun, I apologize)
Yes, a simple oscillator design like this is going to be temperature-sensitive. You could get away with it with vacuum tubes because they generate their own heat and thus are less sensitive to the ambient temperature, but with solid-state circuitry, just putting your finger on the transistor or IC will warm it up enough to cause it to change frequency!
VWestlife yes the unpredictability of it is its weakness but also its charm the prototype i made of my project were all linked together thermally and coverd in heatconducting epoxy to keep it reasonably thermally stable.
VWestlife yes the unpredictability of it is its weakness but also its charm the prototype i made of my project were all linked together thermally and coverd in heatconducting epoxy to keep it reasonably thermally stable.
There are ways to compensate for this. One way is to use resistors with a very specific change in resistance by temperature. They call them tempco resistors. Design your circuit around these tempcos and you can get a stable analog signal within a given temperature range.
Another way is to actually "take charge" of the heating using a heat source and a feedback loop (typically a DAC connected to a CPU). When the DAC tells you you're too cold, you increase the current through the heat source, and when the DAC tells you you're too hot, reduce the current. That way the chip stays at a consistent temperature, regardless of ambient temperature.
Another awesome collaboration, two of my favorite RUclips channels!
Now released: "the Satan AOOT666"
AOOT stands for Always Out Of Tune
This show is magical to me, thanks
This video reminds me that I dropped out of engineering school, lol.
The out of tuneness happens because none of the relevant components are thermally coupled.
No its because of bad circuit design. The adjustment is way too coarse. If one of the pots just drifts by 0.1% the frequency will be off. The adjustment range needs to be much smaller and you need to use low drift components.
I'm talking about the thing going out of tune AFTER it's been tuned.
🍿👀
@@crimsun7186 yeah and potentiometer drif *usually* happens *after* it has been set and in turn will cause it to be out of tune
@Corey Lambrecht nah the fact that he's quiet says enough 😅
That reminds me of a keyboard I built in the 70's, but it didn't have piano keys, just telegraph-style switches.
I came here hoping it used the Atari Pokey chip or something actually Atari related, but its just a Squarewave keyboard
The Atari bit was never properly explained. I thought the same as you that they where using the sound chip from an Atari.
@@kristoffere9996sorry to reply to such an old comment but the name atari junk keyboard is a play on the atari punk console, which is a very simple and common 555 based noisemaker; this is an atari punk console (or a few dozen) made with a junk keyboard, so,, atari junk keyboard 👯♀️
2 of my favorite channels working together, awesome!
EpicLPer yeahhh!!! more collabs!!
top 10 anime crossovers
Thought exactly the same :D Love from Berlin, Germany
EpicLPer i know right!!!
same
5:56 sums up my musical ability.
😭😭
you guys are 2 of my favorite youtube channels, it was epic to see a crossover between them! like many people, i was hoping to hear that atari keyboard make an actual song, so here it is! thanks 8-bit guy/keys :)
it looks like ben's buddy did more of " THE BUILD "
Not saying Felix isn't a really smart person, but Ben is sorta meant to be the "brains" of the show while Felix is the "brawn". They're both really clever and Felix knows a lot more about programming languages than Ben, but he does the dirty work most of the time.
He must regret bringing it in and is happy it's gone lmao
Double thumbs up!!! Very enjoyable to see the collaboration of channels. Thank you for sharing!
god i love felix... his voice is godly... and he knows his shit in linux...
Awesome work guys, love to see collaborative work from my favorite video makers.
5:50 sounds like soundtrack for Crazy bus
First 8-Bit Guy and Techmoan, now 8-Bit Guy and Ben Heck. My life is getting better.
The 8-bit guy and Ben Heck, awesome. Only Techmoan is missing.
I really wanted this to happen when I saw Ben Heck make the keyboard. Perfect collaboration. Thanks for getting a demo of this unique device
nice cooperation : D i love watching your videos. keep it up!
David I love these videos, thank you for what you do.
The sound reminds me of a Stylophone (now there's something you could try out!), terrible, but unique, which is what makes it work, well, 'til it conked out of course... :)
555 chips rely on capacitor discharge time to generate a pulse and if flat ceramic caps are used then the timing will be greatly affected by the ambient temperature.
It sounds like an electronic bagpipe
this is great! I've been a ben heck fan for years, and was featured on one of his episodes.
he claimed back then that he's no good at music and wouldn't do a music-related project - I'm glad he finally did!
They let you write on it?
TrevorJr26 what does it matter its a piece of shit
It's useful for everybody anyways! And even if not, that could probably be erased, and in the end it's his own property now, most likely...
Yeah it sounds awful IMO and it broke on him lol
I mean it WAS his first attempt at building a keyboard, and it did use different circutry than usual.
They gave it to him. It's his, so yes.
Holy crap! I love the Ben Heck Show. I have one of Ben's shirts I won in a can crusher design contest. The ditty was awesome, BTW.
Now that's one keyboard I would not like to play.
Dang... I watched this with headphones on...
Couldn't Ben at least replace the soundchip?
What sound chip? It doesn't have one!
Ha! Triggered :>
Yea but you know what I mean, wish he could have at least modified the sound a little but then again... it broke on you anyway so.
that's a burn son
as I recall from bens vid, it uses the 555 timer chip 4 sound, so other waveforms ar not nearly as easy to do as you would think. and if you say he used 556 not 555, their the same thing, but 556 hat 2 555's in it.
+D-MMA and what might your age be, my fine smart ass?
two of my favourite Retro tech channels working together, amazing
It's like mastering a theremin.
I would LOVE to hear full versions of all the bit songs you make -- they sound amazing
so glad this is your job now!
Awesome collaboration!
Thank God you got one recording out of it, LOL!
Perfect proof of concept!
I guess building 12 oscillators and then dividing down with a flip flop would make more sense. You'd still need some sort of VCA per key then... Part count gets out of hand fast, indeed. Although, old transistor organs did something similar.
I love when my favorite youtubers come together and collaborate!
I still cant understand why someone would dislike???
dude that actually super-jammed. So hard in fact that you annihilated the keyboard. 10/10
"OK, so first off, a little introduction to how this thing works."
It doesn`t
The wonky upper notes sound oddly like a windpipe on your 3-track demo.
I am planning to create my own keyboard, similar to that one but using an ATtiny, polyphonic etc. If I send it to you when I am ready, would you send it back to me later?
L3 P3 lol I always thought the same sending and getting it back think xD
If you want to talk to him about that, you should email him.
use yamaha fm chip
gmod112 Hell yea
Did that ever happen? I'm kinda curious.
They say that when two of your favorite youtubers collaborate on something. A star is born.. :) Fun to see for the rest of us at the very least.. :)
I have thought about it for some time but I got to ask. It would be great to see how you go about composing. I mean, what are your routine go to stuff (key, chord progression, melody relationship to chords)? you have distinct style/ sound to your melodies.
Great collab with Ben Heck When I saw the keyboard i had to think it would be nice if you got to test it, pity you couldn't actually do a whole song on it ^^ but was a great demo!!
Also, absolutely loving the amount of videos you've been pumping out lately man, best luck on your endeavors!
That thing sounds like junk in my ears
at least is a nice horn simulator
Atari junk keyboard.
I like the bass sound
not musically tho
That's why it's called junk keyboard
Cool project. I did something similar to that about 20 years ago. It only used 1 555 timer for a clock source and 4 chips called "top octive dividers". They were intended for the highest octive and to get the next lower octive divide each note by 2, but I divided the clock source by 2 for each octive. I fed each note through a keyboard from an organ to 44 100k resistors as a mixer. I only needed to adjust one pot to tune the whole kb and got full 44 note polyphonic output..
it would be a great cross over episode if you took the keyboard back to Ben and he could get it working again
=^.,.^=!
3:24 no that's not E flat that's the sound the wii makes when it crashes
That keyboard is only good for making the soundtrack of a Taco Bell bathroom...
If you want to see what goes into a single-voice analog synthesizer, with temperature compensation (yes, analog synths tend to go out of tune at different temperatures unless compensated using special tempco resistors), check out MFOS (Music from Outer Space). Ray has passed on, but this Sound Lab Ultimate is still an excellent example of analog electronics. He also has keyboard scanning circuits, noise generators, and more. The schematics and board layouts are all on his site.
Also, analog synthesizers with VCOs (starting in the 80s) typically have tuning logic on-board. It's usually a microcontroller doing some sort of frequency counter stuff and adjusting voltages to compensate.
5:50 Whenever I try to play any instrument
Phaedra by Tangerine Dream is supposed to have started out as a practice demo also! But I don't think the keyboard broke on them. The Moog suddenly starts going out of tune at one point and they mixed it so that it seems like they did that deliberately.
Too bad you can't tumbs-down a thumbs-down and turn it into a thumbs-up.
Was I not completly broke I would support this channel on Patreon. Suscribed and notifications bell on. Keep up the good work.
3:36 Sounds like a printer
this dude sounds like puberty is not over for him
A bit hard on Ben and the build there I thought
Not really, he's just saying as a practical keyboard it's junk as you nead more polyphony and it needs to stay in tune and all that. But he's also saying that as a proof of concept its a really good idea that he enjoyed playing around with. Ben says its not as good as it could be due to his self imposed time limit and design choices to make it a quicker build. He does a llt of projects and cant afford yto get bogged down.
Eh, not really. It was a quick build, it is just a concept. I'm sure Ben and Felix just wanted to see if they actually could build a keyboard before they started building something more advanced and bigger.
It was a bit blunt perhaps, but to be honest, it was kind of a ridiculous design on Ben's part. Especially if they were on a time crunch, it seems like they actually made it way more complicated than it really needed to be, and made it worse as a result.
Daniel G
That I can agree on. There were some things that they could've done better just as fast, but I still think it's an interesting concept with no microchips or anything!
Mmm, jury's out still. I like 8bit guy tons but Ben really knows his stuff so sounded a bit "meh" when in fact with time constraints it was very well executed - and 8bit guy probably couldnt do it himself in that timeframe.
Analogue synths were notorious for going out of tune and changes in ambient temperature, heat or humidity were the main culprits of making a synth go from fine, half an hour ago, to discordant chaos considering it was toasty inside the synth now. Hot and cold days played murder with voltage controlled oscillators.
IC's (LM555's or LM556's) and digitally controlled oscillators finally sorted things out.
You should look at a device called a dub siren. It's a single oscillator squeaky thing (with loads of delay on it) all over reggae records. An LFO modulates an oscillator and makes all manner of mad sounds.
Look for the RUclips vid 'NJD Style Dub Siren - Sound System FX' for a demo if you are interested.
The Ben Heck Show stuff is allways interesting and they have a lot of knowledge- BUT I allways think they put not enough thought in their concepts to make a good result- and than they ALLWAYS rush things an make stuff kind of useless in the end....
I've been building keyboard instruments now for 62 years and this is the weirdest of all. What a fascinating item. Thanks for sharing.
What's so Atari about it?
mario64remix nothing except one of the original designers who came up with the schematics thought it sounded vaguely like a 2600 after they built it and the name stuck. Search "Atari punk console" on Wikipedia if you want more info
prufrockrenegade Thanks for the answer!
COUGH COUGH!!! Original designers my ass....Forrest Mims designed this circuits and published it in a series of cool little electronics schematics book, published in 1980 to look like someones hand drawn notes. At some point some people hit on this circuit and started selling kits of it to make money out of someone else's design, give it a stupid name, and inspire a million numbskulls to make horrendous sounds with this god awful design. I include myself in that. The best thing I ever did was throw away all my 555 chips, although someone did actually manage to make the 555 chip sing, the Thomas Henry 555 VCO is an osciallator worth playing, it;s a much more complicated build than this however (and way more expensive) but if they could build a keyboard that had 4 of those, which could be either across the 4 octaves or put into some unison mode, they would build a serious contender for a worthy synth. Akai released something like that which famously sounded awful at NAMM as it never kept tune at all, all the demo videos are beyond funny, I don't know if they ever released that synth, but surely these guys could build something better than it.
it sounds bad
The pots are logarithmic meaning that at the lower end the ohm values are spread out and at the upper end there are close together. Replace them with linear pots and you'll be able to tune the notes at the upper end.
Ben Heck is a fantastic electrical engineer. All the folks in these comments couldn't do a tenth of what he can do with a soldering iron
yeah. Why is everyone being so harsh to Ben & Felix. It's such an awesome project, and it works quite well. It could've even been shipping that caused it to fail. It doesn't even have a sound chip and it still sounded good.
I doubt 90%+ of everyone watching this video can actually comprehend how to build a keyboard of their own like Ben & Felix did. So much disrespect in the comments. It's like telling an artist their art is shit when it's their first time trying out watercolour; instead of the usual pencil drawings. Ben isn't technically a professional in the field of music, but he is at pretty much everything else to do with electronics. People are being way too harsh
From what I've seen of Ben, he is practically a god at this kind of stuff. I am in awe of what he can do.
That may all be true but this is intended to be a musical instrument, it serves a single purpose and it should be judged by its performance. If someone enginered a midi guitar but didnt bother with proper fretboard then it would be useless defeating the purpose of engineering it.
As a viewer I see this video as showcasing a prototype which is nonfunctional.
awww I miss Ben Heck. His channel was the first channel I binge watched on RUclips. He was my first.
One of the worst keyboard ever built
not if you like experimenting with things. I guess you'd say the Moog synthesisers are bad too.
You were nearly right, it IS the worst
what's wrong with you? it's fucking amazing
is the sound amazing?
555 timers aren't exactly really related to Atari.
very cool. thanx for sharing. glad to see much more often videos on your channels.
One of the most horrible things I've heard lol. Junk tunes on ZX Spectrum 48k sounded better
That was COOL! I remember hearing people in electroncs class toying with the very idea of this. It's neat to see it in operation.
Ben Heck - over complicated and over engineered solutions to problems that do not exist.
He's done some great things, but builds like this just seem pointless.
When just using circuitry without any sort of computronics, you can expect this sort of inaccuracy. That said, this was really neat, and pretty damn sweet.
To be honest, it sounds terrible... ^^'
No offense though, I'm sure it wasn't easy to build!
Radio Shack used to sell a keyboard kit which used *one* potentiometer and a bunch of 5% resistors--I think I got that one for my birthday and it was a real disappointment since it couldn't achieve anything remotely musical. With regard to the BH design, intonation could likely be improved considerably by using smaller capacitors on the higher octave generators (cut the capacitance by about half for each octave). Basically try to use the smallest cap on each generator that will still allow it to be tuned to the correct note. Otherwise, if one wanted full polyphony it could easily be achieved using 12 74HC4060 chips for a chromatic scale, or 7 for a diatonic scale; each chip would provide outputs for one pitch in seven consecutive octaves.simultaneously.
This was a great video but crap keyboard worthy of the dumpster. Time restraints or not Ben Heck but if you're going to build something, DO IT RIGHT!!!!!!.
ThePacratz it was just a fun little project, not a design for commercial use. Most people don’t even know where to begin with a project like this.
This is awesome! You working together with Ben Heck's!
Where does Atari come in place? Did I miss something?
Btw, that is actually an immature and next to useless device. Rather a waste of time, honestly. In respect for the effort involved I hesitate becoming explicit. If you do something, do it right.
I cant remember the details but the keyboard is essentially using the same method to create sound that the old Atari used. This was more a prototype to see if it could be done, a lot of effort but they learnt things and created something interesting.
Waste of time for you, maybe, but not for the people who made it, nor the people who watched the episodes and learnt a lot about simple electronics in the process. The nerve of some people...
ComandanteJ
Please don't get me wrong, I honestly and totally respect the effort and the skills coz I could not achieve anything even close to working status. But this doesn't render the device useful. And srsly no disrespect at all to the creators. But I couldn't say "Great Job!". Could you?
No, of course not, but calling it "a waste of time" is going too far, man!.
"I honestly and totally respect the effort and the skills"
Then act like it, instead of being a pretentious jerk. This isn't something that's supposed to have a utilitarian purpose. It's for fun and also serves as a teaching tool for basic electronics.
"When you turn on the camera, things break", thats true! Last time I was going to make a video, I broke my camera.
3:33 keyboard + printer = keyprinter.
For a final project, I wired up a basic keyboard that had 7(?) keys that also played short tunes that I could find online. Pretty neat
this reminds me a lot of a synth i built in university. the more pots you use, the worse it gets hahaha. i built a very simple 2 oscillator polyphonic synth, wanted to do 2 octaves but even cheap parts are expensive. the polyphony ended up working alright (but adding waves meant you would have to lower amplitude somehow), and i even ended up having it generate some cool polyrhythms as a result of the waves adding the way they did. the synth was glued onto a plank of wood and i think most of the cables are now missing. but watching this was a cool trip down memory lane
Awesome work David! Love your videos! Any chance you might do a review or demos of any of the Roland AX series "keytars" some day? I've seen a pair played live by Freezepop and they were incredible, I'd love to hear your take on them.
A company in Italy called farfisa was building all electronic organs, without the use of any digital circuitry, or even integrated circuits, half a century ago. These devices used initially germanium transistors, which were supplied by Mullard of the UK, and eventually switched to modern silicon transistors. Schematics are readily found on the internet, and they are excellent examples of electronics as an art form. Even today, surviving units are prized because of what is called the farfisa sound.
Sounds like a bagpipe synth
A 555 timer chip depends on an external capacitor / resistor hystereses to induce oscillation within the 555 chip. If the components used for this are physically small the tuned frequency will change not only as a result of ambient temperature but also as the components warm up with use. This will be most noticeable if the cap is a ceramic type because then ambient humidity will increase this effect. The only way to stabilize a 555 timer IC is to replace the capacitor with a crystal. This would prevent tuning in all but harmonics of the natural crystal frequency. The 555 IC is a linear circuit with a digital output. The linear portion of the 555 are affected by temperature changes as well.
The high octave tuning sensitivity problem could be solved by using linear potentiometers rather than logarithmic pots.
The effect of two keys side by side pressed at the same time resulting in the played note being approximately one octave higher is because you are applying two of the tuning pots in parallel to a single 555 timer IC. This effectively divides the resistance in half and rises the oscillation frequency of the capacitor by a factor of 2 (or one octave)
Two problems here: 1, there is a resistance scaling problem due to nonlinearity of the RC time constants thru-out the musical range (5-8 octaves). 2, the octave allocation is asynchronous or random with the keying input. Diode isolators are needed between resistors so adjacent notes don't interfere with each other by altering the RC time constants (reducing resistance).
The way the notes within a single group combine makes perfect sense if you consider the way that resistors in parallel behave. :)
Trent Reznor could probably appreciate a synth like this, he uses a Swarmatron quite frequently in his music, it doesn't have much electronics, just a spider circuit board with relays and knobs.